Feeder for automatic screw machines



March 7, 1944. W, BOCHENEK 2,343,364

FEEDER FOR AUTOMATIC SCREW MACHINES Filed March 4. 1943 Patented Mar. 7, 1944 s PATENT OFFICE FEEDER FOR AUTOMATIC SCREW MACHINES Walter H. Bochenek, Chicago, Ill. applicati@ March 4,1943, serial No. 471,923

5 claims. (c1. zes-s2) This invention relates to improvements in feeders and more especially a feeder for automatic screw machines, forming or cutting-off machines, and the like.

In feeders of the character referred to, it has been customary to provide a member with resilient fingers for gripping the stockwhich ordinarily is a bar, circular in cross-section, or of other shape. The gripping has ordinarily been accomplished by frictional engagement between the lingers and stock and diiculty has beenencountered owing to the fact that with too much friction the stock was scratched or scored, and with too little friction the feeder would not operate properly. y l

Among the features of my invention is the provision of a feeder including a carrier with a reciprocating collet therein and means operating automatically to increase the grip of the collet on the stock during the forward movement of the feeder and diminish the same during the backward or recovery movement.

Another feature of my invention is the provision of an improved feeder that can readily be attached to any standard automatic screw machine, or the like, in place of the conventional feeder now being used, without substantial changes, alterations or adjustments.

Another feature of my invention is the provision of a feeder in which the collet can be readily removed, permitting the substitution of other collets of different sizes, that is, with di-fferent bores, thus permitting quick and easy adaptation of the feeder to operate on stock of various sizes and shapes.

Other features and advantages will appear more fully as I proceed with my specification.

In that form of device embodying the features of my invention, shown in the accompanying drawing, Figure l is a view in side elevation; Figure 2 is a view taken as indicated by the line 2 of Figure l; Figure 3 is a view taken as indicated by the line 3 of Figure 2; Figure 4 is a view taken as indicated by the line 4 of Figure 2; and Figure 5 is a view similar to Figure 2. showing the parts in an altered position.

As shown in the drawing, the feeder comprises a tubular carrier I having one end threaded into the tube II, which is a reciprocating member of conventional feeding mechanism. I2 indicates the stock, here shown as a round bar. It is to be understood that the members I0 and I l move back and forth in a conventional manner in feeding the stock. More particularly, it may be stated that the carrier I0 moves forwardly, to the left, for the feeding stroke to feed the stock I2 a suiiicient distance into the machine for one operation. The member Ill is then moved backwardly, or retracted to the right for the recovery stroke during which time the stock I2 remains stationary. The cycle is then repeated.

Inside of the carrier I0 is a reciprocable collet I3 with three resilient stock gripping fingers I3a. 'I'he forward ends of the fingers l3nt are thickened as indicated byv I3b, the portions between I3a and I 3b being beveled or tapered as indicated by I3c. The forward inner endof the carrier I Ilis also tapered as indicated by Illcto engage the' tapered portions I3c of the ngers sothat whenthe collet I3 is moved rearwardly (to the right) with respect to the carrier I, the fingers will be pressed against the stock I2, and when it is moved in the reverse direction, they will be released.

The fingers I3a are resilient or springy and preferably are formed so that they Will always frictionally engage the stock I2 to some extent. This friction is suiiicient so that as the carrier I0 moves back and forth, the collet I3 Will reciprocate therein. Consequently, as the carrier ID moves forwardly during the feed stroke, the surfaces Ic and I3c will engage to close the fingers more tightly against the stock; and on the recovery stroke the surfaces Illc and I3c will become disengaged so that there will be less pressure of the fingers against the stock.

Reciprocation of the collet I3 in the carrier I0 is limited in one direction by the lugs I3d carried by the extensions I3e. The lugs I3d operate in slots Illa in the carrier I0, and the ends of these grooves or slots are engaged by the lugs I3d to limit the reciprocating stroke of the collet I3 in the carrier I0 to the left as viewed in Figure 5.

The extensions I3e are somewhat springy and the sides of the lugs I3d are beveled, as indicated by I3f. These engage beveled surfaces Ib in the slots I0a so that the collet can be easily removed by rotating the same to the right (viewed in Figure 4). This rotation causes the lugs I3d to be sprung inwardly to release the same from the slots, permitting removal of the collet from the carrier ID. It is to be understood that this removal is accomplished when the stock I2 is removed. In this manner other collets with difierent sizes of bores may be easily substituted in order to adapt the feeder to stocks of various sizes and shapes. Rotation of the collet in the carrier, under normal conditions, is prevented by the location of the lugs I3d in the slots Illa.

While I have shown and described certain embodiments of my invention, it is to be understood that it is capable of many modifications. Changes, therefore, in the construction and arrangement; may be made without departing from the spirit and scope of the invention as disclosed in the appended claims, in which it is my intention to claim all novelty inherent in my invention as broadly as` permissible, in view of the .prior art.

What, I claim as new, and desire to secure by Letters Patent, is:

1. A feeder of the character described, including: a, carrier; a colletl reciprocablymount-e'diin the carrier; resilient feeding fingers on the collet,-v cooperating beveled surfaces on thecarrier; andA feeding fingers respectively, whereby reciprocations of the collet in the carrier' cause' alternate tightening and loosening of said fingers;A alculie-y tudinal slot in the carrier; and a spring extension on the? colletv having` a, lugadapted to' be received by andi 'to be* longitudinallyl movable f in said slot, the lug. and slot cooperating to prevent rotation of the* colletl irr the'carrier duri-ng feeding and' being" the solev means for maintaining the collet` in operative position` inthe carrier; e

2. Afeeder of the character described, including.; a: carrier? a c'ollety' reciprocab'ly mounted; in` the carrier;A resilient;4 feeding fingersl on one end* of* the collet; cooperating beveled surfacescnA the carrier' andi feeding fingers respectively; whereby reci'procati'onsr of' the' collet' in the: carrier cause alternatgtightelfngand'looseningof said; 'n'gers; longitudinal' slots in.. the carrier; and spring ex,- tenslonson the otherendxofjlthecoliet having lues' on tire-ends' ltllereof)adapted?tio bie received brand` 10 4, Apparatus of the character claimed in claim 2, wherein said lugs have transversely beveled surfaces, whereby forced rotation of the empty collet releases the lugs from the slots.

5.. A feederof the character described consist- 15mgof only two pieces and including: a carrier,

ai milletV reciprocably mounted in the carrier; re-

silientL feeding ngers on one end of the collet; cooperating beveled surfaces on the carrier and feedingngers, respectively, whereby reciproca- 20 tions of' the collet-l in the carrier cause alternate tightening and? loosening of said". fingers; longitudinali slots. in thecarrier; and? spring extensionsV on the other `end of" the collet havin-gv lugs on the ends thereof adapted to be received by g5 and to4 be longitudinally movable in said slots,

theamount of possiblel longitudinalvr movement of saidlugsf in said slots being greaterthan the movement-1 required for thel alternate tighteningand loosening of the feed-ing iingershe-lugs and 3o slots cooperatingfto prevent rotationr of theN collet in; they carrier during feeding and being the sole means for maintaining the-collet in operative pesitiorrv inv the carrier,` but saidi` lugs. having-4 transversely beveled surfaces, whereby*` forced rotation 35 of the. empty collet releases the lugs from th-eslots.

H. BOCHENEK. 

